Passengers are being reassured that the rail network is safe following checks on points similar to those at the centre of the Cumbria train crash.
Network Rail said it had found nothing of concern after checking a sample of around 700 points across the country.
Firm conclusions about the cause of Friday's crash near Kendal, in which an 84-year-old woman died, are unlikely to be revealed for some months.
But accident investigators will release an initial report on Monday.
The inquiry is focused on a set of points which the Virgin Pendolino train ran across before the accident.
Network Rail has acknowledged that there might have been a points failure and took the precautionary measure of checking around 700 of 4,000 to 5,000 similar sets of points across the country.
The points, known as Westinghouse type 63, are generally used only in emergencies and normally have a stretcher or fixed bar which keeps the rails apart.
John Armitt, Network Rail's chief executive, said: "The additional checks were a precautionary measure that any responsible organisation would carry out.
"Passengers should be reassured that our investigation has shown nothing out of the ordinary at any location we have visited."
He added: "Our maintenance teams will continue with the day and night job of maintenance, including the visual inspections of points on a regular basis."
Mr Armitt said he expected the initial findings of the Department of Transport's Rail Accident Investigation Branch (RAIB) to be given to him on Monday.
A spokesman for Network Rail confirmed that the area where the accident took place had a variable line speed of 80-95mph.
He stressed that 95mph - Virgin's estimate of the speed of the train at the time of the crash - was a safe speed for a Pendolino.
Ch Supt Martyn Ripley, of the British Transport Police, said the operation to recover the train's carriages was a "logistical nightmare", and that heavy duty lifting equipment would not be on site until at least early Tuesday.
Thomas Edwards, who is leading the inquiry for the RAIB, said two black box data recorders had been recovered from the wreckage and information from them would now be analysed.
The points were "essential to the investigation", he said, but added the inquiry would also be looking at three other main areas - the track between the points and where the train slipped down the embankment, signal boxes and the train itself.
He also said a "statement of fact" would be issued within seven days but that the full investigation would take "months".
Potters Bar comparisons
Meanwhile there have been calls for an independent public inquiry into the crash.
Louise Christian, the solicitor who represented victims of the 2002 Potters Bar crash, in which seven people died when a train derailed following a points failure, said not enough had been done since then to improve rail safety.
British Transport Police: National police force for railways, also covers London Underground and Midland Metro Tram System
Rail Accident and Investigation Branch: Investigates incidents on railways to improve safety - does not establish blame.
Her Majesty's Railway Inspectorate: Division of the Office of the Rail Regulator, oversees safety on Britain's railways and tramways
She said that instead of an inquest into the deaths of the victims of the Potters Bar crash, due to be held on 23 April, there should be "a public inquiry into both [crashes] and to look at the maintenance of the track and the points".
Former Transport Secretary Alistair Darling ruled out a public inquiry into Potters Bar but Network Rail and the line maintenance company Jarvis later admitted civil liability in relation to the crash.
Ms Christian's comments came after rail expert Christian Wolmar told BBC News 24 the points on which the Cumbria crash probe was focusing could have had loose bolts.
"From what I understand, they have found these points in a similar condition to those at Potters Bar, with some missing nuts and the stretcher bar, which keeps the rails properly apart, apparently loosened," he said.
The train's carriages slipped down an embankment after the crash
Shadow chancellor George Osborne told Sky News the Conservatives had concerns over whether there was enough co-operation between rail companies and those responsible for maintaining the track.
Train driver interviewed
Work at the crash site itself, which is accessed via narrow rural roads, has been hampered by rain which has caused the scene to become very muddy underfoot.
Cumbria Police helpline: 0800 056 0146
Police family liaison centre: 0800 40 50 40
National Rail Enquiries: 08457 48 49 50
A forensic examination carried out by the British Transport Police, the RAIB and Her Majesty's Railway Inspectorate (HMRI) is expected to continue at the site for several days.
Margaret Masson, 84, of Glasgow, died after the crash, and eight people were seriously injured, including Mrs Masson's daughter and son-in-law Margaret Langley, 61, and Richard Langley, 63.
Both are in a serious but stable condition at the Royal Preston Hospital.
Richard Blakemore, 54, from Reading, and Graeme Stewart, 28, an IT consultant originally from Glasgow but now living in London, are both said to be in a "comfortable" condition.
Another patient has been transferred to another hospital to undergo neurosurgery by brain and spinal consultants.
Iain Black, the train driver, suffered a broken collar bone and a broken bone in his neck, his union Aslef has said, and is expected to remain in hospital for about a month. He is in a serious but stable condition.
Ch Supt Ripley said investigators had spoken to Mr Black, and that he would be interviewed again.
Five other patients are being treated at other hospitals in the region while most of the other 60 people who were injured have now been discharged.
Virgin Trains said the line may not reopen to passenger services until during the week beginning 5 March.